Well-documented crypto APIs for trading, wallets and data.
BitAzure builds the API layer for exchanges, custodians, data providers and fintech products: REST, WebSocket and FIX interfaces with consistent authentication, rate limiting, idempotency, versioning, signed webhooks, generated SDKs and a developer portal that makes integration predictable.
- REST, WebSocket and FIX interfaces on one gateway
- Market data, trading, wallet, custody and blockchain data APIs
- HMAC and OAuth authentication with quotas and idempotency
- OpenAPI specs, TypeScript and Python SDKs, sandbox environments
What is crypto API development?
Crypto API development is the design and implementation of programmatic interfaces that expose market data, order execution, wallet and custody operations, and blockchain state to external developers and internal systems. It covers protocol choice (REST, WebSocket, FIX), authentication and authorisation, rate limiting, versioning, event delivery through webhooks, and the specifications, SDKs and documentation that make the interface usable.
BitAzure builds APIs for exchanges, brokers, custodians, payment providers and data businesses. A typical engagement produces a gateway with consistent cross-cutting behaviour, a set of domain services behind it, a webhook dispatcher with delivery guarantees, a sandbox that mirrors production semantics, and a developer portal with key management and interactive documentation.
Good APIs are contracts. We treat the OpenAPI or FIX specification as the source of truth, generate SDKs and validation from it, and version it deliberately so partners can upgrade on their own schedule without surprises.
Crypto API development capabilities
These services can be delivered together as a complete API platform or individually into an existing exchange, wallet or data stack.
API Protocols
- REST APIs with consistent resource and error models
- WebSocket streams with subscriptions, heartbeats and resume
- FIX 4.4 and FIX 5.0 sessions for institutional order flow
- gRPC for internal service-to-service calls
- Protocol-specific rate limits and backpressure
Market Data & Trading APIs
- Order-book snapshots and incremental depth updates
- Trades, candles, tickers and funding data
- Order placement, amendment, cancel and batch endpoints
- Account, position and fill history queries
- Post-only, reduce-only and time-in-force semantics
Wallet, Custody & Blockchain Data APIs
- Address generation, deposits and withdrawals with policy checks
- Custody operations with approval workflows
- Balances, transfers and token holdings across chains
- NFT metadata, ownership and transfer history
- Transaction status, confirmations and reorg handling
Authentication & Traffic Control
- API key and HMAC request signing with timestamp windows
- OAuth 2.0 for partner and delegated access
- Rate limiting and quotas per key, tier and endpoint
- Idempotency keys for safe retries on mutating calls
- IP allow-lists and key scopes
Webhooks & Eventing
- Signed webhook payloads with rotation-friendly secrets
- Retries with exponential backoff and dead-letter queues
- Event replay and delivery logs for partners
- Ordered delivery per resource where required
- Outbox pattern so events always match committed state
Specifications, SDKs & Developer Experience
- OpenAPI specifications as the source of truth
- Generated TypeScript and Python SDKs
- Versioning with deprecation schedules and changelogs
- Sandbox environments with deterministic test data
- Developer portal with key management, docs and usage metrics
Reference crypto API platform architecture
Cross-cutting concerns live in the gateway, domain logic in dedicated services, and events flow out through a dispatcher, so each API surface can evolve without touching the others.
Hover or focus a component to see its role in the architecture.
- Clients & SDKs (TypeScript · Python · FIX engines): Partner systems, trading bots and internal apps calling through generated SDKs or raw protocol clients.
- Developer Portal (Keys · docs · usage): Self-service key management, interactive OpenAPI reference, changelogs and per-key usage dashboards.
- API Gateway (Auth · rate limit · WAF): HMAC and OAuth validation, quotas, idempotency cache, schema validation and WAF rules applied uniformly.
- Webhook Dispatcher (Signed · retries · replay): Consumes domain events, signs payloads, delivers with backoff and records every attempt for partner replay.
- REST Service (Resources · pagination): Request-response endpoints for accounts, orders, wallets and blockchain data with generated validation.
- WebSocket Service (Streams · fan-out): Subscription management, heartbeats and resumable streams for market data and private updates.
- FIX Gateway (Sessions · drop copy): Session management, sequence recovery and order-flow translation for institutional counterparties.
- Core Services (Trading · wallet · indexer): Matching, wallet and custody backends and chain indexers reached through internal gRPC interfaces.
- Event Bus (Kafka): Durable domain events feeding WebSocket fan-out, webhooks and analytics.
- Data Stores (PostgreSQL · Redis · ClickHouse): Transactional state, idempotency and rate-limit caches, and columnar history for queries.
Edge
- Authentication and signing
- Rate limits and quotas
- WAF and IP policies
API surfaces
- REST resources
- WebSocket streams
- FIX sessions
Core services
- Trading and accounts
- Wallet and custody
- Chain indexers
Delivery & tooling
- Webhook dispatcher
- OpenAPI and SDKs
- Sandbox and portal
Where crypto APIs are built
Exchange public APIs
Market data and trading interfaces for retail, algorithmic and institutional clients.
Custody and wallet-as-a-service
Programmatic address management, transfers and policy-controlled withdrawals for platforms.
Blockchain data products
Balances, transfers, token and NFT data delivered as a commercial API.
Payment and settlement integrations
Merchant and PSP integrations with webhooks for deposit and settlement events.
Institutional connectivity
FIX sessions and drop copies for brokers, OEMS vendors and funds.
Partner and white-label platforms
OAuth-scoped access so partners can embed trading or wallets in their own products.
Why teams build their API layer with BitAzure
Consistency by design
Shared conventions for errors, pagination, signing and versioning across every endpoint.
Safe retries
Idempotency keys and outbox-based events mean partners can retry without duplicate orders or missed updates.
Predictable evolution
Versioning with deprecation timelines and changelogs so integrations do not break silently.
Fast partner onboarding
Generated SDKs, sandboxes and interactive docs shorten the time to a first successful call.
Operational visibility
Per-key metrics, latency percentiles and webhook delivery dashboards for support and capacity planning.
Security in the gateway
Signing, scopes, allow-lists and WAF rules applied uniformly before any request reaches domain logic.
Technologies we use for crypto API development
Node.js
BackendEvent-driven APIs, gateways and real-time WebSocket services.
Go
BackendConcurrent network services, relayers and infrastructure daemons.
TypeScript
FrontendStrict typing across the entire stack, client to contracts tooling.
Python
BackendData pipelines, quant research tooling and AI services.
PostgreSQL
DatabaseTransactional ledgers, ledgers-of-record and analytical workloads.
Redis
DatabaseCaching, sessions, rate limiting, pub/sub and order-book snapshots.
Kafka
DatabaseDurable event streaming between engines and services.
ClickHouse
DatabaseColumnar analytics for trade history and market data.
Kubernetes
InfrastructureAutoscaling, rolling deployments and workload isolation.
AWS
InfrastructureEKS, RDS, KMS, CloudHSM and multi-region deployments.
Prometheus / Grafana
InfrastructureMetrics, dashboards and alerting for every service.
The Graph / Indexers
BlockchainCustom indexers and subgraphs for fast on-chain queries.
How we deliver an API platform
Every engagement follows a documented, milestone-driven path from discovery to continuous development.
- 01
API discovery and contract design
Consumers, use cases and protocols are mapped, then the OpenAPI and FIX specifications are drafted and reviewed with stakeholders.
- 02
Gateway and cross-cutting policies
Authentication, rate limiting, idempotency and versioning are implemented once in the gateway and covered by contract tests.
- 03
Service implementation
REST, WebSocket and FIX surfaces are built against the specification with generated validation and mocks.
- 04
Webhooks, sandbox and SDKs
Event delivery, a deterministic sandbox and TypeScript and Python SDKs are generated and tested end to end.
- 05
Developer portal and documentation
Key management, usage dashboards, guides and interactive references are published for internal and external developers.
- 06
Launch, monitoring and lifecycle
Progressive rollout by partner tier, SLO dashboards, and a managed deprecation process for future versions.
Security practices in API development
Request signing
HMAC signatures with timestamp and nonce validation to prevent replay and tampering.
Scoped credentials
Keys and OAuth tokens carry explicit scopes, IP restrictions and expiry, with withdrawal permissions separated from trading.
Edge protection
WAF rules, bot mitigation and rate limits enforced before requests reach application code.
Webhook integrity
Signed payloads, secret rotation and replay windows so receivers can verify every event.
Input validation
Schema-based validation generated from the specification, with fuzzing of parsers and FIX message handling.
Audit and monitoring
Structured access logs, anomaly alerts on key usage and full traceability from request to domain event.
We coordinate independent third-party audits on request and never claim an audit, certification or compliance status unless it has actually been obtained.
What to decide before building a crypto API
Protocol fit
REST suits request-response workflows, WebSocket suits streaming, and FIX is expected by institutional counterparties. Most platforms need all three with shared semantics.
Rate-limit policy
Limits must protect the matching engine and nodes without blocking legitimate high-frequency clients; tiered quotas and weighted endpoints are common.
Consistency guarantees
Decide whether reads are strongly or eventually consistent and document it, particularly for balances and order state.
Versioning strategy
URL, header or field-level versioning each have trade-offs; the deprecation policy matters more than the mechanism.
Sandbox realism
A sandbox that behaves differently from production causes integration failures at launch; invest in deterministic but faithful test data.
Partner support model
Public APIs create a support surface; usage analytics, status pages and clear error messages reduce ticket volume.
Crypto API Development questions
REST for account management and order placement, WebSocket for market data and private order updates, and FIX for institutional clients whose systems already speak it. Sharing one order model and one authentication scheme across all three keeps behaviour consistent.
Designing an API your partners will build on?
Send us your use cases and existing systems. We will return a proposed specification outline, gateway design and delivery plan.